The United States, the United Kingdom, and Norway have signed a statement of intent to outline principles of cooperation on the P-8A Poseidon maritime reconnaissance aircraft.

The statement was signed on the outlines of the NATO defense ministers meeting in Brussels on Thursday.

Norway and the UK are set to start operating the Boeing-built maritime patrol aircraft after the first aircraft arrive in 2019.

With the signing of this agreement, the three countries established a framework for further cooperation in areas such as readiness, enhancing defense capability, and interoperability.

The P-8A is a derivative of a modified Boeing 737-800ERX airliner with antisubmarine and anti-surface warfare capabilities. The armament of the Poseidon consists of five internal and six external stations for AGM-84H/K SLAM-ER, AGM-84 Harpoon, Mark 54 torpedo, and a High Altitude Anti-Submarine Warfare Weapon system among others.

Development of the P-8A program was started in June 2004 when the U.S. Navy selected the Boeing multimission maritime aircraft, 737 MMA, as the best successor to the P-3C Orion maritime patrol aircraft.